Flawed studies on breast cancer and dietary fat

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What the mainstream media doesn't want you to know.

The recent study that low fat diets don't prevent breast cancer in a large cohort of women now confirms similar results of another large study, the Nurses' Health Study at Harvard. But this interpretation for these hugely expensive studies is seriously misleading and is more about the way we investigate and publicize the dietary fat and breast cancer relationship than it is about the results obtained.

Both studies were prompted by a major 1982 National Academy of Sciences (NAS) report that was the first major document to recommend cutting fat consumption from 40% of calories to 30% to prevent cancer risk, a report that I co-authored. But the researchers who subsequently organized these two very large studies misinterpreted our report's findings, then designed studies that were seriously flawed, despite recommendations to the contrary.

Aside from their recommendation on fat, the committee also advocated increased consumption of "fruits, vegetables, and whole grain cereal products" but cautioned that this did not apply to the effects of individual nutrients. They made clear that the 30% fat recommendation was arbitrary and was only meant as a "practical target" to monitor dietary change, adding that the evidence on fat even suggested, "the[sic] data could be used to justify an even greater reduction". Together, these recommendations emphasized the effect of whole foods on cancer risk, not the effects of individual nutrients.

Unfortunately, the investigators of these two large studies failed to comprehend these recommendations on two accounts. Both groups initially sought my views -- in seminars and discussions -- but I was disappointed to learn that their very narrow hypothesis was inconsistent with the NAS report and was not likely to provide useful information. They preferred investigating the singular effects of fat on breast cancer while mostly ignoring the much more promising effects of a diet replete with fruits, vegetables and whole grain products that was naturally low in fat. It was my view that this was too narrow and not likely to be useful.

This narrow focus on fat reflected a sense of simplicity that was inconsistent with the underlying biology. At about the same time these studies were being organized, a similar approach to control cancer was being vigorously pursued by others who hoped to develop and market supplements of individual nutrients, a market that ultimately became exceptionally lucrative. Both of these strategies have now been proven to be ineffective.

These were hypotheses of gimmickry that reflected huge market forces at play. Modestly decreasing fat from certain well-entrenched foods allowed their continued marketing. Popping a few nutrient pills or adding dietary fiber to foods created new market opportunities.

This gimmickry primarily arose from an intense aversion to the evidence showing that it was the imbalanced consumption of animal and plant based foods that mattered most. There was a strong tendency to ignore this evidence, both within our NAS committee and by the investigators who were organizing these large human studies on breast cancer. Our committee, for example, decided on the arbitrary and practical target of 30% fat because a lower level, which was supported by the evidence, would have implied decreased consumption of meat, milk and eggs that might cause public rebuke of the entire report.

The available evidence for our NAS committee showed that the association of dietary fat with breast and other cancers was attributed to the consumption of animal protein, reflecting excessive consumption of animal based foods, perhaps also inadequate consumption of plant based foods. Laboratory evidence, including our own, also was showing that consuming animal protein had multiple adverse health effects. It could markedly increase cancer development, elevate blood cholesterol and atherosclerotic plaque and induce loss of calcium needed for strong bones. But all of this evidence was minimized and ignored, and continues even today. This also was a personal challenge for me. I was raised on a dairy farm milking cows, then started my research career at Cornell University attempting to promote more not less animal protein consumption.

This negation of the evidence has had serious consequences. For example, the vast majority of subjects in both of these recently reported studies used diets rich in animal protein, total fat and animal based foods, leaving virtually no opportunity to experimentally investigate the effects of a diet of whole plant based foods naturally low in fat. Women who consumed less fat, actually consumed more animal protein. Indeed, they were urged and coached to do this. At best, these women only made minor changes in fat consumption, leaving intact their imbalanced consumption of foods likely to make the most difference.

Now, using meager findings to make sweeping generalizations to dismiss the effect of diet on serious diseases like cancer only compounds the problem. Indeed it is deeply irresponsible for it denigrates some recent work from clinicians that, in fact, we are what we eat. Nothing in my 50 years in research is more promising than the brilliant work of Caldwell Esselstyn, Jr., MD, of the Cleveland Clinic showing that a truly low fat, plant based diet is able to CURE heart disease, an effect that also is beginning to appear for other diseases as well.

Researchers need to be more attentive to the American taxpayer who foots the bill for their work, regardless where this research may proceed. Unfortunately, in the current climate, doing such research seems to be more about creating wealth for the few at the expense of the health of the many.

T. Colin Campbell, PhD, is Jacob Gould Schurman Professor Emeritus of Nutritional Biochemistry, and Author, with T. Campbell, of The China Study (2005) Learn more about Dr. Campbell and his book at www.TheChinaStudy.com

Editorial note: The above article is from the co-author of the NAS Report which prompted these dietary fat/cancer studies which have been so widely covered in the US media. Of interest is that this article was submitted to almost every major newspaper in the United States, and all rejected it. Outlets such as The New York Times, Washington Post, Chicago Tribune and many others were uncomfortable printing this article which provides evidence that the real (and ignored) health story is that a plant-based diet is being shown to be the key to preventing or reversing serious disease, including cancer. Instead, each of these publications ran paid advertisements from the Dairy Council and the National Cattlemen's Beef Association in the same timeframe. When government research is owned by corporate interests, and the mainstream media is as well, it's hard to get much accurate information, be it information about political issues, about issues of war, or about issues of health.